Support for electrical display device

ABSTRACT

A support for an electrical display device such as a monitor is disclosed. The support includes a pair of support members ( 2,3 ) connected by a pivot joint ( 4 ) to enable relative movement of the support members ( 2,3 ) about an axis of rotation, the joint ( 4 ) including an outer hub ( 11 ) mounted for rotation about the axis within a clamping member ( 5 ) attached to one support member ( 2 ), an inner hub ( 10 ) mounted to the other support member ( 3 ) coaxial with the outer hub ( 11 ) and being rotatable about the axis relative to the outer hub ( 11 ) in a first direction and, a clutch member ( 12 ) between the inner and outer hub ( 10,11 ) engageable in response to rotation of the inner hub ( 10 ) in the opposite direction such that the outer hub ( 11 ) rotates together with the inner hub ( 10 ) when a compressive force exerted on the outer hub ( 11 ) by the clamping member ( 5 ) is overcome. A universal joint ( 7 ) is also disclosed.

The present invention relates to a support for an electrical displaydevice such as flat screen computer monitor that enables the display tobe oriented in any desired position to suit the viewer.

Supports for flat screen computer monitors are known and generallycomprise a pair of support arms pivotally connected together. A free endof one arm is mounted to a wall or is formed with a sleeve to enable itto be mounted to an uptight support post clamped to a desk orworkstation. The free end of the other a=m is usually attached to asupport plate via a universal joint to enable the screen to be locatedin any desired position. The back surface of the display screen isattached to the support plate via a quick release mechanism to enablethe screen to be detached from the arm for repair or replacement

The pivot joint connecting the arms together must be designed so that itis sufficiently stiff to hold and maintain the monitor in a set positionbut free enough so that a user can manipulate the joint when a force isapplied thereto. When the monitor is to be moved, it is usually graspedin both hands and pushed and/or pulled into the desired position so thata frictional force between a member on one arm pivotally connected toanother member on the other arm is overcome allowing the members torotate relative to each other. It will be appreciated that thefrictional force between the members must be sufficient to ensure thatthe weight of the display monitor and the arm to which it is attachedcannot cause the members to rotate relative to each other without theapplication of an outside force by the user as this would result in themonitor dropping under its own weight due to gravity. As displaymonitors can be relatively heavy, this presents the problem that thepivot must be relatively stiff to generate the requited frictional forcebetween the members. This results in the user having to apply aconsiderable force to the monitor to move it and overcome the frictionalforce at the pivot joint. This problem is particularly noticeable whenthe monitor is to be raised as the user then has to catty the weight ofthe monitor and arm to which it is attached as well as overcome thefrictional force at the pivot joint.

Although the aforementioned problem can be addressed by providing areleasable clamp to lock and unlock the pivot joint, this is undesirableas the clamp must then be unlocked each time the monitor is moved andlocked again afterwards. This means that a tool to release and tightenthe joint must be provided or incorporated in the pivot joint which isnot always easily accessible.

It is an object of the present invention to overcome or substantiallyalleviate the problems with a conventional support for a display deviceaddressed above.

According to the present invention, there is provided a support for anelectrical display device such as a monitor including a pair of supportmembers connected by a pivot joint to enable relative movement of thesupport members about an axis of rotation, the joint including an outerhub mounted for rotation about the axis within a damping member attachedto one support member, an inner hub mounted to the other support membercoaxial with the outer hub and being rotatable about the axis relativeto the outer hub in a first direction and, a clutch member between theinner and outer hub engageable in response to rotation of the miner hubin the opposite direction such that the outer hub rotates together withthe inner hub when a compressive force exerted on the outer hub by theclamping member is overcome.

It will be appreciated that the present invention provides a pivot jointin which the frictional force is only active in one direction ofrotation of the arm connected to the monitor to hold it in position andprevent it from dropping under gravity due to the weight of the monitorThe force that must be overcome is generated by the damping memberagainst the outer hub, the outer hub rotating with the inner hub andrelative to the clamping member when the inner hub is rotated in onedirection only. When the arm is rotated in the other direction, theinner hub rotates relative to the outer hub and the clamping member andso the force clamping the outer hub does not need to be overcome.Therefore, when the monitor is lifted, there is no or little frictionalforce that must be overcome at the pivot joint and so the monitor ismuch easier to move to the desired position.

Preferably, the clutch member comprises a coiled element disposed aroundthe inner hub such that the inner hub rotates relative to the coiledelement in the first direction, the coiled element being drawn radiallyinward toward the axis of rotation in response to rotation of the innerhub in the opposite direction such that it binds and rotates with theinner hub, the coiled element being connected to the outer hub such thatthe outer hub rotates together with the coiled element. As the clutch isoperable in response to rotation of the inner hub in a specificdirection, there is no locking arrangement that must be actuated beforethe user can move the monitor.

In a preferred embodiment, each support member is an arm, one end of afirst arm having mounting means thereon for attaching it to a wall or asupport post, the remote end of said first arm being connected to oneend of a second arm by the pivot joint which allows the second arm topivot up and down in a vertical plane.

The support conveniently includes cooperating means for connecting theclamping member to the first arm, the damping member having a beatingseat to receive and locate the outer hub and the cooperating means beingconfigured to enable the compressive force exerted on the outer hub tobe adjusted.

Advantageously, the cooperating means is also configured to enable theclamping member to pivot about a second vertical axis relative to thefirst.

In a preferred embodiment, the coiled element is disposed in an annularspace formed between the inner and outer hub.

Conveniently, the coiled element is a spring.

The support preferably includes attachment means on one end of thespring and on the outer hub for attaching the spring to the outer hub.The spring and outer hub are attached to each other so there can be norelative rotation between them.

The attachment means preferably comprises a hook portion on the springand a notch in the outer hub, the hook portion and notch cooperatingwith each other to attach the spring to the outer hub. The hook portionis preferably a very tight fit in the notch.

As mentioned above, the end of one of the support arms is attached tothe display screen via a universal joint to enable the screen to belocated in any desired position. The universal joint may comprise a balland socket type joint. However, a disadvantage wit conventional ball andsocket type joints is that the display monitor has limited movementbecause the socket in which the ball is received fouls the arm to whichthe ball is attached when a particular angle is reached therebypreventing positioning of the screen in a chosen location. Furthermore,assembly and manufacture of the universal joint is generally complex dueto the number of components involved.

It is also an object of the present invention to substantially alleviateor overcome the problems addressed in the previous paragraph,independently of the problems addressed earlier, and provide a supportfor a display device having a universal joint that is considerably moreflexible and has a much wider range of movement.

According to another aspect of the invention, there is provided asupport for an electrical display device such as a monitor including apair of support members connected by a universal joint comprising a partspherical bearing immovably mounted on one support member and receivedwithin a bearing seat pivotally mounted to the other support member toenable relative movement between the bearing and the bearing seat in anydirection and, between the bearing seat and the other support memberabout a pivot axis.

In one preferred embodiment, the bearing seat comprises a looped elementor strap that partially encircles the bearing, the ends of the loopedelement being pivotally mounted to the other support member. The strapadvantageously has an arcuate beating surface on its inner face where itcontacts the spherical bearing. The width of the strap is sufficient toretain the bearing within the arcuate bearing surface.

Conveniently, corresponding apertures are formed in the ends of thelooped element and the support member to receive a fastening member topivotally attach the looped element to the support member so that acompressive force is exerted by the looped element on the bearing. Thisis necessary to ensure that the bearing and looped element will onlymove relative to each other when a force is applied thereto by a userotherwise the monitor would drop under its own weight.

Preferably, a resilient material layer is disposed between at least oneend of the looped element and the support member to enable thecompressive force exerted on the bearing to be adjusted by tightening orloosening the fastening member.

In a preferred embodiment, one support member is a support arm and theother support member is a support plate to receive and mount a displaydevice.

The bearing is preferably immovably mounted to the support plate and thebearing seat is pivotally mounted to the support arm to enable rotationof the beating seat about the pivot axis.

Advantageously, the support plate includes a mounting surface for thedisplay device and a socket to receive and immovably mount the bearing.

The bearing and support plate may be integrally formed.

In an alternative embodiment, the being is immovably mounted to thesupport arm and the bearing seat is pivotally mounted to the supportplate.

Preferably, the support arm comprises a pair of parallel support legs,the legs being spaced from each other by the bearing.

In one embodiment, wherein the support plate includes a mounting surfacefor the display device and a head portion to pivotally mount the beatingseat thereto for rotation about the pivot axis.

It will be appreciated that the two different aspects of the inventionmay be employed independently or together in the same display support

Embodiments of the present invention will now be described, by way ofexample only, with reference to the accompanying drawings, in which:

FIG. 1 shows a partial perspective view of a monitor support accordingto an embodiment of the invention;

FIG. 2 shows an exploded perspective view of one of the arms and pivotjoint of the monitor support illustrated in FIG. 1;

FIG. 3 shows a partially assembled view of the arm and pivot joint shownin FIG. 2;

FIG. 4 shows an enlarged perspective view of an alternative universaljoint arrangement to that shown in the support of FIG. 1;

FIG. 5 shows a partial exploded perspective view of a modifiedembodiment of a monitor support arm according to the invention; and

FIG. 6 shows a partial assembled perspective view of the modifiedembodiment of FIG. 5.

Referring now to the drawings, there is shown in FIG. 1 a support 1 foran electrical display device (not shown) having first and second supportarms 2,3 connected by a pivot joint 4 having a generally C-shapedcamping member 5 connecting the first and second support arms 2,3together. Each support arm comprises a pair of parallel support legs 2a, 2 b, 3 a, 3 b. A universal joint 6 is mounted to the remote end 7 ofthe second support arm 3 and is connected to a support plate 8 to whicha display monitor may be releasably attached via a quick releasemechanism (not shown). The construction of the universal joint 6 will bedescribed in more detail late. The free end of the first support arm 2(not shown) is attached to a bracket or a sleeve to enable the support 1to be mounted to a wall or located on an upright support post (notshown) clamped to a desk or workstation.

The construction of the pivot joint 4 will now be described in moredetail. The support arm 3 may rotate relative to the support arm 2 abouta pivot axis indicated by A in the drawings. Referring primarily to FIG.2, a boss 9 extends from the support leg 3 a to immovably receive andlocate a cylindrical inner hub member 10 having its longitudinal axiscoincident with the pivot axis A. The other support leg 3 b also has anidentical boss (not shown) which is received in an opening 9 a in theopposite end of the inner hub 10. The support legs 30 b and inner hub 10are secured together with a bolt (not shown) that extends through anaperture 10 a in the inner hub 10 and the legs 3 a, 3 b, the legs 3 abeing parallel to each other and spaced by the inner hub 10.

In one alternative unillustrated arrangement, the cylindrical inner hub10 may be integrally formed with one of the support legs 3 a, 3 b.

The inner hub 10 is coaxially located within an outer hub 11 in the formof a cylindrical ring having its longitudinal axis coincident with thepivot axis A. It will be apparent that the outer hub 11 has a largerdiameter than the inner hub 10 so that the inner hub 10 will fit withinthe outer hub 11.

A clutch member in the form of a coiled spring 12 is disposed around theinner hub 10 in an annular space 13 (see FIG. 3) formed between theinner and outer hubs 10,11. The inner diameter of the coiled spring 12is only just greater than the diameter of the inner hub 10 to allow theinner hub 10 to rotate in one direction whilst the spring 12 remainsstationary. One end of the spring has a bent back or hooked portion 14and the outer hub 11 has a corresponding notch or cut out 15 to receivethe hooked portion 14 when the spring 12 is received between the innerand outer hubs 10,11, thereby connecting the spring 12 and outer hubtogether so that they cannot rotate relative to each other in eitherdirection.

The clamping member is generally C-shaped although the two ends almostmeet to form a complete ring but are spaced by a distance X for reasonsthat will become apparent. A radially extending flange 17,18 having anaperture 19 therethrough is formed at each end of the damping member 5.

The outer hub 11 is received within the clamping member 5 as shown inFIG. 3. The clamping member 5 is then attached between support legs 2 a,2 b, as shown in FIG. 1, using a bolt that extends through the supportlegs 2 a, 2 b the apertures 19 in the flanges 17,18. The bolt istightened so that the distance X between the flanges 17,18 is reducedand the clamping member tightens around the outer hub 11 so that theouter hub can only rotate within the clamping member 5 when thecompressive force applied to the outer hub 11 by the clamping member 5is overcome. It will be appreciated that the clamping member may alsopivot about an axis indicated by B in FIG. 1, at right angles to thefirst axis indicated by A and extending through the bolt mounting theclamping member 5 to the support arm 2.

Operation of the pivot joint will now be explained. When the arm 3 isrotated about the axis A in an upward direction indicated by arrow C inFIG. 3, the inner hub 10 rotates relative to the spring 12 and the outerhub 11 to which the spring 12 is connected remains stationary.Therefore, the user does not have to overcome the friction between theouter hub 11 and the clamping member 5 to rotate the arm 3 relative tothe other arm 2 about the pivot axis A. However, when the arm 3 isrotated in the opposite downward direction indicated by arrow D in FIG.3, the coils of the spring 12 tighten and are drawn radially inwardlyand so bind against the surface 10 b of the inner hub 10. Furtherrotation of the arm 3 causes the inner hub 10 and the spring 12 torotate together. As the spring is connected to the outer hub 11 via thehooked portion 14 and notch 15, the outer hub 11 also rotates. However,as the outer hub 11 is in frictional engagement with the clamping member5, the force preventing the outer hub 11 from rotating must be overcomebefore the inner hub 10 and therefore the arm 3 will rotate. It is thisforce that prevents the arm and the monitor to which it is attached frompivoting under gravity due to their weight.

The universal joint 7 will now be described in more detail. As shown inFIG. 1, a substantially spherical bearing 20 is mounted between the legs3 a, 3 b at the end of the arm 3 opposite to the pivot joint 4. Thespherical beating 20 is immovably held between the legs 3 a, 3 b by abolt (not shown) that extends through an aperture 21 in the legs 3 a, 3b and through the spherical bearing 20. The spherical beating 20 mayhave flattened regions 22 where it meets the legs 3 a, 3 b.

A shaft 23 upstands from the rear of the support plate 8 and has a discshaped head 24 attached thereto. A C-shaped connecting strap or loop 25passes around the spherical bearing and is attached to the disc shapedhead 24. The strap 25 has an arcuate beating surface 26 that contactsthe spherical bearing 20 and is wide enough to retain the sphericalbearing within the bearing surface 26. The ends 27, 28 of the strap 25are connected to either side of the disc shaped head by means of a bolt(not shown) that extends through an aperture 29 in the ends 27, 28 ofthe strap 25 and through an aperture in the disc shaped head 24 so thatthe head 24 can rotate with respect to the strap 25 about an axis Eextending through the bolt. It will also be appreciated that the strap24 together with the head 24 and support plate 8 can move relative tothe support arm 3 in any direction about the spherical bearing 20.

An alternative arrangement for the universal joint 7 is illustrated inFIG. 4. In this embodiment, the spherical bearing 20 is immovablymounted between arms 30 mounted to the back of the support plate 8. Thestrap 25 then loops around the spherical bearing 20 and is attached toeither side of a support arm 3 using a bolt (not shown) that extendsthrough the apertures 29 in the ends of the strap 25 and through anaperture in the end of the arm 3. The strap 25 may then pivot about thearm 3 about an axis F and the support plate 3 and spherical bearing 20may move relative to the strap 24 in any direction.

It will be appreciated that, in both of the aforementioned embodiments,the strap is located relatively tightly around the spherical bearing 20so that relative movement between the strap 24 and the bearing 20 willonly occur when a user applies a force to the joint. The compressiveforce applied to the spherical bearing 20 by the strap 24 may becontrolled by adjusting the tightness of the bolt connecting the strapto the head, in the first embodiment, and tightness of the boltconnecting the strap to the arm 3 in the alternative embodiment.

To provide additional control of the degree of movement, a resilientlycompressible washer (not shown) may be located between the ends of thestrap 24 and the component to which it is attached so that the washerwill compress as the bolt is tightened and enable the pressure appliedto the spherical bearing to be adjusted easily.

In the embodiment of FIG. 4, the support arm 3 is formed from a singlemember rather than a pair of parallel support legs. However, it will beappreciated that the embodiment could be adapted for use with an armbeing formed from two legs such as that shown in FIG. 1.

Referring now to FIGS. 5 and 6, there is shown a modified support armaccording to a second embodiment of the invention. As with the firstembodiment, the modified support arm has first and second support arms2,3 each comprising a pair of parallel support legs 2 a,2 b,3 a,3 bconnected by a pivot joint 4. The pivot joint 4 is identical to that ofthe first embodiment except that the boss 9 has been replaced by anelongate protruberance 40 on each of the support legs 3 a,3 b and thecylindrical inner hub member comprises a pin 41 having a radiallyextending slot 42 in either end thereof to receive the protruberance 40when the support is assembled and a nut 43 is located through aperturesin the support legs 3 a,3 b and the pin 41. The hooked portion 14 of thespring 12 now extends parallel to the axis of rotation and locates in acorresponding axially extending recess in the outer hub 11.

The universal joint 6 at the other end of the support legs 3 a,3 b hasalso been modified. As can be seen from FIG. 6, the head 24 of thesupport plate 8 now incorporates an integrally formed hexagonal boss 44immovably mounted thereto so as to extend through a circular aperture 45a in the strap 25. Referring now to FIG. 5, the strap 25 includes a pairof rings 45 each having hexagonal openings 46 which locate over thehexagonal boss 44. Each ring 45 has a rim 47 that seats around theperiphery 48 of the aperture 45 in the strap 25. A flat spring washer 49is located over each ring 45 and a nut 50 fastens the assembly togetherwhich tightens against the hexagonal boss 44 on the head 24 of thesupport plate 8. The support plate 8 is therefore held fixed due to thefriction between the rings 45 and the periphery 48 of the aperture 45and this friction must be overcome when the support plate 8 is movedrelative to the strap 25. This arrangement is an improvement because thefriction between the rings 45 and the periphery 48 of the aperture 45 isgenerally constant and the ability to move the support plate 8 is lessdependent on the tightness of the nut 50.

It will be apparent that the present invention provides a pivot jointbetween two arms that makes it much easier to position a monitorattached to the end of the arms. It also provides a flexible and easy tomanufacture and assemble joint that enables the monitor to have a verywide range of movement.

Many modifications and variations of the invention falling within theterms of the appended claims will be apparent to a person skilled in theart and the foregoing description should be regarded as a description ofa preferred embodiment only.

1. A support for an electrical display device including a pair ofsupport members connected by a pivot joint to enable relative movementof the support members about an axis of rotation, the joint including anouter hub mounted for rotation about the axis within a clamping memberattached to one support member, an inner hub mounted to the othersupport member coaxial with the outer hub and being rotatable about theaxis relative to the outer hub in a first direction and, a clutch memberbetween the inner and outer hub engageable in response to rotation ofthe inner hub in the opposite direction such that the outer hub rotatestogether with the inner hub when a frictional force exerted on the outerhub by the clamping member is overcome.
 2. A support for an electricaldisplay device according to claim 1, wherein the clutch member comprisesa coiled element disposed around the inner hub such that the inner hubrotates relative to the coiled element in the first direction, thecoiled element being drawn radially inward toward the axis ofrotation-in response to rotation of the inner hub in the oppositedirection such that it binds and rotates with the inner hub, the coiledelement being connected to the outer hub such that the outer hub rotatestogether with the coiled element.
 3. A support for an electrical displaydevice according to claim 1, wherein each support member is an arm, oneend of a first arm having mounting means thereon for attaching it to oneof a wall and a support post, the remote end of said first arm beingconnected to one end of a second arm by the pivot joint which allows thesecond arm to pivot up and down in a vertical plane.
 4. A support for anelectrical display device according to claim 3, including flanges forconnecting the clamping member to the first arm, the clamping memberhaving a bearing seat to receive and locate the outer hub and theflanges being configured to enable the compressive force exerted on theouter hub to be adjusted.
 5. A support for an electrical display deviceaccording to claim 4, wherein the flanges are configured to enable theclamping member to pivot about a second vertical axis relative to thefirst arm.
 6. A support for an electrical display device according toclaim 2, wherein the coiled element is disposed in an annular spaceformed between the inner and outer hub.
 7. A support for an electricaldisplay device according to claim 6, wherein the coiled element is aspring.
 8. A support for an electrical display device according to claim7, including attachment means on one end of the spring and on the outerhub for attaching the spring to the hub.
 9. A support for an electricaldisplay device according to claim 8, wherein the attachment meanscomprises a hook portion on the spring and a notch in the outer hub, thehook portion and notch cooperating with each other to attach the springto the outer hub.
 10. A support for an electrical display deviceincluding a pair of support members connected by a universal jointcomprising a part spherical bearing immovably mounted on one supportmember and received within a bearing seat pivotally mounted to the othersupport member to enable relative movement between the bearing and thebearing seat in any direction and, between the bearing seat and theother support member about a pivot axis.
 11. A support for an electricaldisplay device according to claim 10, wherein the bearing seat comprisesa looped element that supports and partially encircles the bearing, theends of the looped element being pivotally mounted to the supportmember.
 12. A support for an electrical display device according toclaim 11, comprising corresponding apertures formed in the ends of thelooped element and the support member to receive a fastening member topivotally attach the looped element to the support member so that acompressive force is exerted by the looped element on the bearing.
 13. Asupport for an electrical display device according to claim 12, whereina resilient material layer is disposed between at least one end of thelooped element and the support member to enable the compressive forceexerted on the bearing to be adjusted by tightening or loosening thefastening member.
 14. A support for an electrical display deviceaccording to claim 10, wherein one support member is a support arm andthe other support member is a support plate to receive and mount adisplay device.
 15. A support for an electrical display device accordingto claim 14, wherein the bearing is immovably mounted to the supportplate and the bearing seat is pivotally mounted to the support arm toenable rotation of the bearing seat about the pivot axis.
 16. A supportfor an electrical display device according to claim 15, wherein thesupport plate includes a mounting surface for the display device and asocket to receive and immovably mount the bearing.
 17. A support for anelectrical display device according to claim 15, wherein the bearing andsupport plate are integrally formed.
 18. A support for an electricaldisplay device according to claim 14, wherein the bearing is immovablymounted to the support arm and the bearing seat is pivotally mounted tothe support plate.
 19. A support for an electrical display deviceaccording to claim 18, wherein the support arm comprises a pair ofparallel support legs, the legs being spaced from each other by thebearing.
 20. A support for an electrical display device according toclaim 18, wherein the support plate includes a mounting surface for thedisplay device and a head portion to pivotally mount the bearing seatthereto for rotation about the pivot axis.
 21. (canceled)